CVE-2026-8161 Details
Description
[email protected] and lower versions are vulnerable to denial of service via uncaught exception. By sending a multipart/form-data request with a field name that collides with an inherited Object.prototype property such as __proto__, constructor, or toString, the parser invokes .push() on the inherited prototype value rather than an array, throwing a TypeError that propagates as an uncaught exception and crashes the process. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: none. Upgrade to [email protected] or higher.
A denial-of-service vulnerability has been identified in the multiparty package, specifically in versions through 4.2.3. The issue arises from prototype pollution, where a multipart/form-data request includes a field name that conflicts with an inherited Object.prototype property, such as __proto__, constructor, or toString. This collision causes the parser to mistakenly invoke the .push() method on the inherited prototype value instead of an array, leading to a TypeError. This error propagates as an uncaught exception, crashing the process. Any service that accepts multipart uploads using multiparty is vulnerable.
Users are advised to upgrade to multiparty version 4.3.0 or higher.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed May 12, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://cna.openjsf.org/security-advisories.html | openjs | Third Party Advisory |
| https://github.com/pillarjs/multiparty/security/advisories/GHSA-qxch-whhj-8956 | openjs | Vendor Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-1321 | Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') | openjs |
| CWE-248 | Uncaught Exception | openjs |
Affected Products
| Product | Versions |
|---|---|
| pillarjs multiparty | < 4.3.0 |
CPE
Remediation
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Change History
4 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | openjs |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| May 13, 2026 | Initial Analysis | [email protected] |
| May 12, 2026 | New CVE Received | openjs |